A gas mixture consisting of $9\mathrm{.}7$ kmol of methane $($CH$4)$ and $2\mathrm{.}15$ kmol of nitrogen $($N$2)$ with $20\%$ excess air When burned, partial combustion occurs and $3\mathrm{.}7$ kmol of carbon monoxide $($CO$)$ is formed in the flue gas. is formed. Calculate the mole $($in kmol$)$ amounts of other gases in the flue gas and the flue gas Determine the percentage composition.